Nearly three years after it began, the case of a Massachusetts man convicted in an Irish Republican Army weapons plot linked to the Lehigh Valley has been appealed to the U.S. Supreme Court.

Lawyers for defendant Richard Johnson are asking the Supreme Court to declare unconstitutional two laws that led to his conviction and to overturn the conviction. The court has never reviewed either law.

Johnson, Christina Reid and Martin Quigley were convicted in 1990 of conspiring to develop military rockets, bomb detonators and other advanced weapons to use against British targets in Northern Ireland. Each is serving time in federal prisons.

Quigley, an Irish citizen, supposedly used Bethlehem and Wilson as a base of operations. A fourth defendant, Gerald Hoy of Palmer Township, pleaded guilty.

Johnson's lawyers, including the noted appellate lawyer Alan Dershowitz of Harvard Law School, asked the court April 28 to review the case.

The court is likely to decide whether to accept the case in its October term. The other defendants did not appeal.

Last December, a federal appeals court upheld the convictions that resulted from the federal trial in Boston.

In calling the two laws unconstitutional, Johnson's lawyers claimed they allowed federal officials to violate the defendant's right of free expression, his right against unreasonable searches and his right to due process.

One law makes it a crime to possess written material used to commit a crime in aid of a foreign power. The defendants supposedly had designs for weapons.

The other law allows courts to grant approval for federal officials to secretly monitor people's actions for foreign intelligence purposes.

The law banning the written material is too broad and too vague, Johnson's lawyers said.

"The criminalization of the willful possession of papers in aid of a foreign government poses a serious threat to American citizens' basic right to speak out and participate in matters of international concern," the lawyers wrote.

"An individual could be charged under (this law) with possession of Abbie Hoffman's `Steal This Book,' a collection of suggestions on how to obtain restaurant meals, long-distance telephone service and other goods and services without paying for them," the lawyers wrote. "The reader/possessor might not share the intent of the author, but might nonetheless be deemed in violation of (the law)."

The other law, the Foreign Intelligence Surveillance Act, or FISA, is unconstitutional because it allows courts to approve electronic eavesdropping without requiring probable cause and without requiring the disclosure of factors that led to the court approval, even during a trial, the lawyers said.

Because it does not require disclosure, Johnson has had "no realistic opportunity to attack the validity of the surveillance, or the evidence it produced, either at trial or on appeal to the Court of Appeals," the lawyers wrote.

FISA allows the government to compromise a defendant's rights by "shrouding a criminal investigation in the cloak of national security," they wrote.

Johnson is serving a 10-year prison term -- the longest ever issued in the United States in a case related to the Irish struggle.